The true dog of the military. Black Hayate was a little
puppy that Fuery picked up on a rainy street one day out of
pity. Since he couldn’t keep the dog himself (living in a
dorm that didn't allow pets), the puppy was eventually
adopted by Riza Hawkeye, who proceeded to freak out the
puppy (and all of Mustang's staff) by shooting an outline of
bullets around it (not hurting it) when it urinated on the
office wall. Despite Riza's harsh methods of discipline,
Hayate is a way for her to show her more compassionate side,
as opposed to the cool, stone-faced officer that she usually
is. Roy has also tried to interact with Black Hayate, with
varying degrees of success. Hayate did manage to get on
Mustang's bad side at least once: when he indirectly wasted
Mustang and his company's time at what they thought was a
murder scene. Mustang and his men had begun excavation of
the site searching for the bones of a dead man, only to
discover that the lot was where Black Hayate buried the
bones from his meals. "Hayate" means Hurricane.
-divinedragonking